There have conventionally been photographic printing paper products manufactured by coating photographic layers on a polyolefin resin-laminated paper support; paper supports of this kind have often been used in recent years because they do not allow processing solutions to permeate thereinto and thus they are suitable for speeding up the processing.
The above-mentioned polyolefin resin generally contains an inorganic white pigment such as titanium oxide or calcium carbonate in order to increase not only the whiteness and hiding power of the support but also the resolusion and sharpness of the photographic emulsion layer. However, when the polyolefin resin is moltenly extruded at a high temperature to be laminated on a paper support, if the inorganic pigment content of the resin is excessive, uneven dispersion of the pigment occurs, so that the allowable inorganic pigment content limit is ten-odd per cent at most, and thus it has still not attained technical feasibility for obtaining satisfactory sharpness.
Japanese Patent-Publication Open to Public Inspection (hereinafter abbreviated to JP O.P.I.) Nos. 27257/1982 and 49946/1982 disclose techniques for providing a photographic paper support having thereon a laminated resin layer cured by electron beam irradiation. If such a support is used, the white pigment content of its resin can be increased by 20 to 70% by weight, leading to improving the sharpness to be much better than that in the polyolefin resin lamination.
It has been found, however, that if a photographic paper laminated with such a high-white-pigment-content resin layer is processed in an automatic processor equipped with a conventional cut-transport-type printer, transport trouble can possibly occur depending on the processing condition.